Power-operated handsaw



Mar. 3, 1925.

R. L. BARKER POWER OPERATED HANDSAW- Sheets-Sheet 1 Original File dfJa'n. 5, 1921 Patented Mar. 3, 1925.

RA'gMONDL. BARKER, OF CHICAGO, ILLINOIS.

POWER-OPERATED HANDSAW.

Application filed January 3, 1921, Serial No. 434,538. Renewed July 19, 1923.

To all whom it may concern:

. Be it known that I, RAYMOND L. BARKER, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a-certain new and useful Improvement in Power-Operated Handsaws, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a. part of this specification.

This invention relates to power-operated hand saws, and more specifically to oweroperated hand saws having guards a apted to protect the saw blades.

An object of my invention is to provide a power-operated hand saw having a ard for the saw blade thereof, the guard eing adapted to be displaced from its protecting position when the saw is brought into operative relation with the work.

Another object of my invention is to pro- 'vide a saw of the class described having a saw blade guard which is adapted to be collapsed by engagement with the work.

A further object of my invention is to provide a saw of the class described, having a saw blade guard adapted to bear upon and be displaced by the work, the guard comprising an anti-friction device, which contacts with the work.

These and other objects of my invention will be more clearly pointed out as the following description progresses, reference being had to the accompanying drawings, wherein Figure 1 is acentral longitudinal section of my improved power-operated hand saw.

Figure 2 is a plan view of my improved power-operated hand saw, a cover plate being removed for the purpose of clearer illustration.

Figure 3 is a sectional view taken on line 33 of Figure 1, looking in the direction of the arrows.

Figure 4 is a fragmentary .central longitudinal section showing a modified form of my invention. 1

Figure 5 is an end elevation of the modificd form of my invention shown in Figure 4.

, Figure 6 is a sectional view taken on line 66 of Figure 4, looking in the direction of the arrows.

Figure 7 is an enlarged fragmentary sectional view taken on the same line as Figure 4, but showing certain details in section which are shown in elevation in Figure 4.

Figures 8 and 9 are detailed views illustrating the manner in which my invention may be applied to a power-operated file or .hack saw.

Similar characters of reference indicate similar parts throughout the several views.

Referring to Figure 1, the reference character 10 designates the casing of my improved power-operated hand saw, the saw blade being indicated at 11. The casing 10.

preferably comprises two members 12 and 13 secured to each other by bolts 14, the members 12 and 13 being adapted to form a hollow handle 15, and a chamber 16. Disposed in the chamber 16, and rigidly secured to the members 12 and 13 by bolts 17 is an electric motor 18. Energy is supplied to the motor 18 by a conductor 19 originatin at any suitable source of power. The con uctor 19 enters the handle 15 at its lower end. A switch 20 conveniently disposed in the handle 15 is placed in series with the motor to provide means whereby the operation of the device ma be controlled. Bearings 22 and 23 forme integrally with the members 12 and'13, a half of each bearing being a part of each of the members, rotatably ournal the motor shaft 24. Keyed to the upper end of the shaft 24 is a crank plate 25, having a crank pin 26. One end of a crank arm 27 is pivotall secured to the crank pm 26, the other end being pivotally connected to a rod 28 by a. pin 29. The rod 28 is slidably journaled in a bearing portion 30 extendmg from and formed integrally with the casing member 12. It is apparent that the motor 18 when in operation will reciprocate the rod 28 by means of the crank plate 25, the crank pin 26 and crank arm 27 As shown in Figure 3, the rod 28 is preferably rectangular in cross section to insure alignment of therod 28. The casing is provided with a sha ed to conform to the rectangular cross,

section of the rod 28 is adapted to be drawn upon the rod 28, and to rest against the end resting against a ring 52, and the other fiange 35. Rigidly' secured to theinner end ofthe saw blade 11 byrivets 39 is a plug 40, which is threaded into the coupling 36. This construction permits adjustment of the blade 11 relatively to the plane of rotation of the crank plate 25, as the plug 40 need not draw the coupling 36 tightly against the flange 35. It also permits the alternate use of cross cut and rip saw blades, as well as the use of other tools which are illustrated in the drawings, and hereinafter described.

The saw blade 11 is protected frominjury by a guard 45 comprising a cylindrical tube 46 rigidly secured to a flange 47 of the bearing portion .30. The tube 46 is disposed around the outer end of the bearing portion 30. A plurality of tubes indicated at 48, 48,

48, and 48 are adapted to successively telescope within one another, the tube 48 telescoping within the tube 48, on so on. The tube 48 is adaptedto telescope within the tube 46. Means comprising compression springs 49, 49, 49 and 49 are provided for holding the tubes in an extended position relatively to each other, the springs tending to force the tubes apart along their several axes, which are substantially coincident. The springs '49, 49*, 49 and 49 are disposed around the tubes 48, 48*, 48 and 48 respectively. Each of the tubes 46, 48, 48, and 48 is provided at its outer end with an inwardly extending flange 50 which serves to retain a ring 51 interposed in each instance between the larger and smaller tubes of any pair of immediately associated tubes. Each ring 51 functions to guide the smaller tube and to stop a similar ring? 52, rigidly secured to the smaller tube. of the springs 49, 49 49 and 49 has one against a similar ring 53 disposed inside of the larger tube of its associated tubes,

and slidably journaling the smaller tube. A.

plurality of fingers 54 projecting inwardly rom the walls of the outer tubes serve to prevent longitudinal displacement of the. rings 53 by the several springs. It is readily understood that each of the springs forces the tube about which it is wound in an outwardly direction, the rings 51 limiting the movement of the tubes in this direction. In their extended position, the tubes are adapted to protect the saw blade from injury, and also to prevent injury to the operator when the blade is reciprocating, but not in actual use.

Each p The outer end of the tube 48, which oc' cupies the most extended position relatively to the casing 10 is provided with an outwardly extending flange 55. The flange 55, co-acting with a ring 56, disposed around the tube 48, retains and journals a plurality of metallic balls 57.

;As the several tubes enclose the saw blade, the balls 57 will engage any work with which the sawis brought into operative relation. The operator will apply a comparatively light pressure in a longitudinal direction relatively to the saw blade, and the several springswill permit the tubes to telescope within one another, thereby unsheathing the blade. However, one or more of the balls will remain in contact with the surface of the work, and lessen the friction between the casing and the work as the operator guides the saw blade.

In Figures 4, 5, and 6, I have illustrated a modified form of my invention, in which a guard is provided for the saw blade 11, but does not completely encircle it. Aboaring portion 30, a rod 28, and coupling means whereby thesaw blade 11 is secured to the rod-28 are shown, the several parts being-similarin detail to the respective parts of the preferred form of my invention. A

pair ofsleeves 60-60 disposed around and of its ends interposed between the head of the bolt 64' and the peripheries of the sleeves 6060, the plate 65 being apertured to permit the shank of the bolt 64 to pass through it. Referring to Figures 5 and 6 it will be noted that the plate 65 is provided with a air of inwardly extending side flanges, 66-66, which converge toward each other, and'toward the saw blade 11. At this point in the description, it is well to point out that if the blade 11'is adjusted about the axis of the rod 28, and therefore relatively to the plane of its associated crank plate (not shown), the plate 65 may beadjusted by means of the bar 63, and the bolt 64, to occupy the same position relatively to the blade as is shown in the drawings. This will permit the plate 65 and its hereinafter described associated plates 69, 69, 69 and 69 to be adjusted to protect the blade at any angle to which it is adjusted. The abovementioned plates are similar in form to the plate 65, and each is provided with side anges similar to the side flanges 6666 of the late 65. The plate 69 with its flanges is a apted to telescope within the plate 65 bal s 76, which and its flanges 66. The remaining plates and flanges are likewise adapted to successively telescope within one another. The

plates are normally forced apart in a longi tudinal direction by compression springs 70,

the outer end of its associated late by rivets 72. Each bar 71 guides the inner plate of each immediately associated pair of plates, and stopsa similar bar 73 secured to the outer side of the inner plate. One end of each spring 70 rests against a bar 73, the other end resting against a similar bar 75 rigidly secured to the outer plate of each pair of lates'. The late 69 is provided with f imction'asdo the balls 57 of the preferred form of my invention.

In Figure 7 I have illustrated the manner in which I prevent the springs 70 from buckling. Projecting from each bar 73 is a rod 73 adapted to telescope into sleeves 7 5" carried by. each bar 75. The springs 70 are disposedaround each pair of sleeves-75" and rods 73.

\Vith the exception of the adjustable feature of the guard relatively to the edge of the saw blade 11, a guard of the modified form of my invention functions similarly to a guard of the preferred form.

Figure 8 shows a file provided with a plug 40*, adapted to be threaded into the coupling 36 of the referred form. of my invention. The file w en so attached to the coupling may be reciprocated, and will be protected from injury when not actually in use.

Figure 9 illustrates a hack saw provided with a plug 40, adapted to be threaded into the coupling 36. The full lines show a hack saw frame suitable for use with the guard,

having plates which do not encircle the saw blade. The hack saw frame may be of the proportions indicated in the dotted lines, thereby permitting the guard to be constructed of a plurality of tubes.

While I have described the details of but two forms of my invention, it is to be understood that my invention is not limited to these details except by the scope of the appended claims.

Vhat I claim is:

1. A ortable power-operated and handmanipu ated and applied tool comprising a reciprocating blade adapted to be advanced endwise of the blade toward a surface of the work, the blade having a. longitudinal sidecuttin edge in combination with a guard norma ly enclosing the entire length of the side edge and so mounted that upon engagement with the word: it may yield longitudinally of the bladet expose the cutting edge to the extent to which said edge penetrates the work.

2. A power-operated hand-manipulated tool comprising a reciprocating blade adapted to be advanced endwise of the blade towards a surface of the work, the blade having a longitudinal side cutting edge in com bination with a guard normally enclosing the entire length of the side edge and so mounted that upon engagement with the work it may yield longitudinally of theblade to expose the cutting edge to the extent to which said edge penetrates the work.

3. A power-operated hand-manipulated tool comprising a reciprocating blade adapted to be advanced endwise of the blade toward a surface of the work, the blade having a longitudinal side cutting edge in combination with a guard normally enclosing the entire length of the side edge, said guard comprising a plurality of telescopic sections and springs operating on said sections to normally force them outwardly from said casing, said guard being so mounted that upon engagement with the work said sectlons may yield longitudinally of the blade to expose the cutting edge to the extent to which said edge penetrates the work.

to act between said frame and the work to support the r001 by the work while the blade is reciprocating.

5. In a unitary portable power-operated saw, the combination of a frame, a handle portion for holding said frame, a rec1p roeating saw blade having a longltudlnal sidecutting edge, a rotary member ournalled o a o 5 I in said frame, a crank drlven by said rotary member, a reciprocating member connecting said crank with said saw blade, means for guiding said saw blade in its reci rocating movement, a work-engaging mem er m ovably supported on said frame, and spring means tending to hold said work-engaging member with the end thereof in proximity to the end ofvsaid sawblade, sald spring. permitting the end of said work-engagm member to move away from the. end of sai saw blade during the cutting operation, said work-engaging member thereby yieldingly supporting the tool on the wor 6. In a unitary portable power-operated saw, the combination of a frame, a rotary member journalled in said frame, a saw havsaid rotary member into reciprocating mopermitting said member to recede from the tion for said saw, a work-engaging member end of said saw. 10 movably supported on said frame, and In witness whereof, I hereunto subscribe spring means normally moving said workmy name this 30th day of December, 1920.

" engaging member into proximity to the end RAYMOND L. BARKER.

of said saw, said spring means cooperating Witnesses: with said work-engaging member to resil- EDNA V. GUs'rArsoN; iently support said frame on the work and IRENE RAsMUssEN. 

